1. Field of the Invention
The present invention relates to a display device and an apparatus and a method for driving the display device, and more particularly to a display device capable of improving a response speed of a liquid crystal and an apparatus and a method for driving the same.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) device poorly displays moving pictures because the response speed of the liquid crystal is slower than a time period corresponding to one frame (referred to as a one frame period), causing a motion blur. The response speed of liquid crystal must be improved to improve the display quality of moving pictures.
To improve a response speed of a liquid crystal of the LCD device, a controller of the display device may operate in an overdrive mode to provide drive current that is either over-compensated or under-compensated (higher or lower) to decrease the time needed to reach a desired brightness. To perform the overdrive mode, a dynamic capacitance compensation (referred to as “DCC”) is generally used to perform the overdrive mode.
When using the DCC, an overdrive value of a gray data corresponding to a preceding frame may be determined by comparing the gray data corresponding to the preceding frame and a gray data corresponding to a current gray data.
When using an overdrive circuit, a look-up table (LUT) that stores measured overdrive values is typically used since the overdrive value determined according to the comparison between the current and previous gray data is not linearly changed according to a gray level due to the property of the liquid crystal. A compensation value (or overdrive value) stored in the LUT is generally measured when the vertical frequency is about 60 Hz and the temperature is a normal temperature.
Variation in operational temperature and/or vertical frequency may affect the overdrive value. Since switching speed and dynamic capacitance change as a function of temperature, a set of compensation values measured at a certain temperature will yield different results at other temperatures.
The compensation value is inversely proportional to the temperature and directly proportional to the vertical frequency. When the temperature increases, the desired brightness may be achieved with a smaller compensation value and when the vertical frequency increases, one frame period is shortened so that the compensation value needs to be increased to achieve the desired brightness.
In order to maintain the response speed of the liquid crystal regardless of the variance in the temperature, a temperature inside of the timing controller may be detected by a temperature sensor (exterior or interior to a display panel) so that a LUT may be used that has the optimized compensation value for the sensed temperature.
However, the chip size increases when the LUTs for respective temperatures are all applied to a memory of the timing controller. Further, heat is generated and a capacity of an external EEPROM is increased.